Measuring pushrods!!

[Makavelli228]

Hello I am new to this forum and this is the first question I am asking. I am building my first engine, its a SBC 355 with vortec heads. I have installed my heads, new oil pump, new Crane Cam 218/228, I have 1.6 scorpion self aligning rockers, and the engine or heads have not been decked (or at least thats what I was told). Anyways, I currently measured my pushrods, one side looks like 7.850 was the right size since the rockers made a mark on the top of the valve in the center of the valve stem. When I measured the other side it looks like its way too long and the line that was made when measuring the pushrods was close to the exhaust side of the engine almost to the tip of the valve tip. Im confused, why is it that one head measures a certain amount and the other measures a different length. Does this mean that one head was milled and the other wasn't? why would this happen and what should I do to fix it.

Anyways, I am thinking that if I get the 7.800 that is stock maybe it might move my right side head that measured 7.850 a little higher than the middle and therefore the other head might be slightly closer to the center. Well any tips or advise will definitely help, thanks in advance.

 

[Fox80]

Welcome to the world of mass produced junk, the block and heads you have are both OEM parts and are nowhere near precise, this is why you zero deck a block it sets the deck height exactly off the crank centerline, in turn the cam centerline as well, this is also why heads are trued up off the centerline of the rocker stud, I have seen blocks have .040 come of one side and only .005 off the other to set the deck height, so it's not impossible for yours to be that far off. Now using two different sets of pushrods side to side might not be the best idea, it may be the only way to fix what you have without pulling the motor apart. Your current set up will be very hard on the valve guides, remember tho it doesn't take much change in length to center the roller swipe back up. I commend you for actually checking it most "motor guys" don't, good luck

 

[Makavelli228]

Hey Fox80 thanks for the reply. Yeah the engine is out of the car at the moment, I wanted to freshen up the engine with better heads, better cam, and a better valve train. I bought the heads from a shop and the guy said that the heads were restored, had a 3 angle valve job and were ready to be installed. Everything so far has gone fairly smooth but this has me confused, not too sure what to do in this situation. Maybe I should pull everything apart and have everything zero decked but i figured id ask before I do so. Thanks again and Im glad to be a part of this forum, G bodies are my favorite rides!!

 

[Makavelli228]

Here is a pic of the pushrod measurements, these are 7.850" stock should be 7.800 but i believe the 1.6 rockers changed the geometry, you can see one side is toward the middle where the other head is toward the exhaust side.

sorry i dont know how to post pics.

 

[Makavelli228]

http://www.flickr.com/photos/59512732@N05/9689229019/

http://www.flickr.com/photos/59512732@N05/9689228971/